1. Field of the Invention
The present invention generally relates to a system that allows voice communications over a LAN network, and more particularly, to a voice communications over LAN network which includes a low bandwidth consuming music-on-hold system that enables music to be provided to callers placed on hold on the LAN.
2. Description of the Prior Art
Music-on-hold is a common feature that has been in use for many years in private branch exchanges (PBX) and automatic call distribution (ACD) systems. In such systems, typically, a B-channel is connected from the music source to the callers. This enables the callers to listen to music while on hold and waiting, for example, their turn in an ACD queue for the next available call center agent. Recently, however, packet-based communications networks are being used for telephony over local area network (ToL) systems, in other words, voice communications over LANs. In particular, a network user is able to pick up a telephone and complete a call to a destination user who may be connected either to the same network server within the network, or to a different server using the public switched telephone network. This is accomplished by converting voice received from the telephone handset into packet data, and sending the packets over the local area network (LAN) to the destination user. The packet data is then converted back into voice at the destination to enable the user to listen to the voice audio on a telephone handset.
In a conventional telephone system, if available connections or trunks to the ACD system run out, users may hear a busy signal and will not be able to establish a connection to the ACD. There is no degradation in performance for those existing callers who had been able to call into the ACD system and subsequently been put on hold. In contrast, in an internet protocol (IP) type system, an almost unlimited number of users may contact the ACD over a single internet pipe. As the number of callers increases, the pipe, or communications lines, becomes increasingly full and all the available bandwidth may be consumed. At that point, the network may crash or become unacceptably slow. In addition, the condition may be exacerbated in ToL systems because an excessive number of callers on hold may cause a network""s available bandwidth to be flooded with packets of music. Thus, there is a need for a bandwidth preserving music-on-hold system for use with ToL.
Briefly, the present invention relates to a system that enables music to be provided to callers placed on hold in a LAN network used for voice communications. Bandwidth consumption is minimized by ensuring that music-on-hold is provided in a manner that enables most necessary tasks to be executed by a client instead of a server, thereby reducing traffic over the network communications lines. In a first embodiment of the invention, when a caller is placed on hold, the music-on-hold system is configured to transfer a small application program or applet, having a music file and a media player, from the server to the client. Concurrently, a real time protocol (RTP) stream carrying music is used to provide music-on-hold to the client from the server during the applet transfer. This ensures that the held caller receives music at all times. The RTP stream is used in the above manner to provide music to held callers in all embodiments of the invention. In another embodiment of the invention, the applet includes only the media player which is transferred from the server to the client. The music provided by the RTP stream is saved by the client as an audio file on a mass storage device for later playback by the media player. In another embodiment of the invention, the media player is built into the client and therefore eliminates the requirement for any files to be transferred from the server to the client. Again, the music provided by the RTP stream is saved by the client on a mass storage device for playback by the media player.
These and other advantages of the present invention will be readily understood with reference to the following specification and attached drawings.